Certain types of watercraft (e.g. ships, aircraft carriers, etc.) are configured with multiple valves situated throughout the vessel. Valve actuators are configured to operate the valves by opening or closing the valves, thereby regulating the flow of fluid through a passageway. Electronic valve actuators can be programmed with positional setting and torque settings to electronically operate the valves between the open and close positions.
Electronic valve actuators have been used in Navy equipment for more than 15 years. First generation electronic valve actuators were often constructed by purchasing rugged commercial power supplies, and then supplying them with one phase of a three phase power supply. Many of these power supplies traditionally used electrolytic capacitors that have a tendency to dry out over years of service. Many of these power supplies also proved to be physically substantial, imposing significant mounting challenges due to their size and weight. Moreover, shock and vibration design requirements often added further size and weight penalties.
In power systems where the valve actuator electric motor is operated by a three phase alternating current (AC) power supply, loss of one of the three phases can result in substantial damage to an electric motor, wiring, and associated electrical mechanical components including damage to the attached valve.
Therefore, it is desirable to detect the loss or disruption of one or more phases of an AC power source before loss of a phase or degradation of the quality of the three phase AC power can cause damage to hardware components.